Polymer—filler interaction has a profound effect on the physical properties of vulcanisates. This interaction regulates the degree of dispersion of the filler, the formation of an elastomer-filler interface and the filler-filler network. All these ultimately will determine the essential physical properties of the compound such as stress-strain properties, energy loss under cyclic load, abrasion resistance, and tear propagation resistance.
Polymer-filler interaction is predetermined by the properties of the polymer (monomer type, co-monomer sequence distribution and molecular architecture) and the filler (chemical nature, particle size, surface area, aggregate structure and surface activity). Introduction of functional groups to the elastomer is one option to improve polymer-filler interaction. Functionalization is either achieved during the polymerization step by the use of a functional monomer, initiator or terminating agent or by post polymerization functionalization of the elastomer. To the former method a great number of recent examples can be found in the literature albeit they are largely limited to living anionic polymerization. Use of silane coupling agents in conjunction with silica fillers is a well-established example of the post polymerization functionalization method, however, use of silanes can lead to increased compound viscosity during mixing.
There is, therefore, a need for an improved method for post polymerization functionalization of elastomers.